[OK, we're working on the 3 laws one at a time. Maybe this groups has a handle on 1/2 law 1].

Robot Knows When It Hits a Person
Assembly Magazine (09/11/08)

Roboticist Sami Haddadin is part of a German Aerospace Center Space
Agency (DLR) research team aimed at transforming industrial robots into smart
machines capable of working alongside humans. DLR is testing the first
industrial robot capable of sensing when it hits someone. Haddadin says that
accidents happen and we have to accept the fact that when people start working
more closely with robots, collisions will occur. To design a safer industrial
robot, DLR researchers tested smashing robotic arms, weighing up to 2.5 tons,
into a crash test dummy at different speeds. To give robots the ability to
detect an impact, Haddadin mimics human's ability to feel blows, which sense the
shock of an impact through specialized stretch receptors in muscles and joints.
In each of the robot's six joints are embedded torque sensors that change their
electrical resistance when under tension in a particular direction. The sensors
give constant feedback on the direction and magnitude of th e forces felt by the
arm, which are used to determine if the robot encounters abnormal forces. Once
the robot detects an impact, it stops and supports its own weight to ensure that
inertia or gravity does not cause further harm to the person. The robot also can
be pushed out of the way using minimal force.
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